When U.S. Customs Department Agent Cliff Holden`s boss is murdered by jewel thieves he`s assigned to the case.Holden vows to apprehend the killers and to destroy the jewel smuggling ring.For this purpose he boards a flight to Europe in order to shadow the main suspect,Matty Royal.On the return flight to America, Holden meets war-bride Kathe van Bourne who`s traveling to the US to meet her American fiancé.Coincidentally,she is wearing a priceless necklace.But Miss van Bourne falls ill on the plane and she is greeted by a mysterious ambulance at the airport.The ambulance whisks her away giving Agent Cliff Holden reason to suspect that his case somehow is connected to Miss van Bourne`s necklace and sudden airplane illness.Holden decides to follow this trail.